Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) Quid Pro Quo Validation Plan

Thomas A. Kovacs and M. Patrick McCormick Hampton University

July 2005

Table of Contents

1. Introduction 1.1 Revision History 1.2 Purpose and Scope

2. Strategy 2.1 Approach 2.2 Data products 2.3 Aerosols 2.4 Clouds 2.5 IIR derived data products

3. Existing Instrument Networks and Individual Sites 3.1 Aeronet 3.2 Asian Dust NETwork (AD-NET) 3.3 Atmospheric Radiation Measurement (ARM) 3.4 Baseline Surface Radiation Network (BSRN) 3.5 Climate Monitoring and Diagnostics Laboratory (CMDL) 3.6 Commonwealth of Independent States Lidar Network (CIS-LiNet) 3.7 EARLINET 3.8 Institut Pierre Simon Laplace (IPSL) Lidar Network 3.9 Micro-Pulse Lidar Network (MPLNET) 3.10 Network for the Detection of Stratospheric Change (NDSC) 3.11 Regional East Atmospheric Lidar Mesonet (REALM) 3.12 USDA MFRSR network 3.13 Individual Sites

4. Coverage of Various Aerosol and Cloud Regions 4.1 Aerosols 4.2 Clouds

5. Implementation 5.1 The QPQ validation milestones 5.2 Communication with sites 5.3 Data Exchange, Storage, and Handling

6. References

7. Appendices 7.1 Latitude, Longitude, and Altitude of all QPQ validation sites. Sites are listed under each network. Some sites are listed under multiple networks 7.2 Map of the 16-day CALIPSO repeating orbit ground-track and the location of all the QPQ validation sites with 80 and 160 km range rings 7.3 Data exchange protocol 1. Introduction

1.1 Revision History

QPQ Validation Plan 0.6 - May 2002 QPQ Validation Plan 1.0 - July 2003 QPQ Validation Plan 1.1 - January 2004 QPQ Validation Plan 1.2 - February 2004 QPQ Validation Plan 1.3 - January 2005 QPQ Validation Plan 1.31 - May 2005 QPQ Validation Plan 1.32 - July 2005

1.2 Purpose and Scope

The quid pro quo (QPQ) measurements in collaboration with existing sites and other activities (e.g. field programs) are an important part of the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) validation program. These sites and field programs will provide data relevant to CALIPSO validation at times when the ground-track of the CALIPSO satellite is within a specified coincident distance. Exchange of data between CALIPSO and these sites will occur with no risk and cost to the project and follow appropriate protocols of exchange. Coordination of the validation measurements will be made through the CALIPSO homepage (http://www-calipso.larc.nasa.gov), the QPQ validation website (http://calipsovalidation.hamptonu.edu), email notices, fax, phone, and conventional mail announcements. This document will describe only permanent sites and not field campaigns sponsored and funded by other groups, although these will be pursued.

Sites are invited to collaborate in the QPQ validation program if data produced at these sites validate CALIPSO Level II data products. The number of coincident measurements, measurement and calibration history of the instruments, publications, and location of data files will be gathered or calculated and stored in a database allowing a user to determine the quality of the measurements and easily find what data are available. A web interface will allow the user to search this database to find data based on their own search criteria.

2. Strategy

2.1 Approach

To a considerable degree, data products from the CALIPSO satellite mission will be validated through comparisons with correlative in-situ and remote sensing measurements. For the CALIPSO mission, validation is defined as an assessment of the accuracy and precision of the derived science products by independent means. Assessment of the relative agreement between data sets can occur either through a direct comparison of two or more measurements or, through a comparison of probability distribution functions (PDFs). Direct comparison implies that the correlative measurements view the same atmospheric features (e.g., same cloud or aerosol layers) as observed by all instruments. In the best of circumstances, the instruments would share the same field of view and occur simultaneously. For ground-based systems, matching measurements with satellite observations can be exceedingly difficult because of the brief window of opportunity during a satellite overpass, and especially for spaceborne lidars or radars, with a very narrow field of view. The difference between two measurements that are not collocated in space or time or have different resolutions will include some measure of geophysical variability, which is unrelated to measurement uncertainty. Fortunately, aerosol air masses can have correlation scales of 50-100 km and several hours or more. For clouds, the length scales can be significantly smaller (a few kilometers to tens of kilometers) and lifetimes as short as a few minutes. These length and time scales, thus, provide guidelines on matching requirements needed between sensor systems for aerosol and cloud features. Trajectory analysis may also be employed to improve matching conditions for observations that have large spatial and temporal separations.

An alternative approach to direct comparisons is to consider an ensemble of observations collected over a long period or a variety of conditions. This approach is especially appealing for geophysical phenomena that have very restrictive matching requirements such as for cumulus clouds.

2.2 Data products

Table 1 lists the primary Level 2 data products that will be produced by the CALIPSO satellite mission. Details on these products are provided in the Lidar and Infrared Imaging Radiometer Algorithm Theoretical Basis Documents (ATBDs). The table also provides information on the expected uncertainty and the horizontal and vertical resolution of the products. Correlative measurements of comparable or superior accuracy and resolution should be acquired to validate these CALIPSO data products.

Table 1: CALIPSO Level 2 Aerosol and Cloud Measurements

Data Product Measurement Capabilities and Data Product Resolution Uncertainties Horizontal Vertical Aerosols Height, thickness For layers with β > 2.5 x 10-4 km-1 sr-1 5km 60 m Optical depth, τ 40% * 5 km N/A

Backscatter, β a(z) 20 - 30% 40 km Z < 20 km 120 m 40 km Z ≥ 20 km: 360 m

Extinction, σa(z) 40 % * 40 km z < 20 km 120 m 40 km z ≥ 20 km: 360 m Clouds Height For layers with β > 1 x 10-3 km-1 sr-1 1/3, 1, 5 km 30, 60 m Thickness for layers with τ < 5 1/3, 1, 5 km 30, 60 m Optical depth, τ within a factor of 2 for τ < 5 5 km N/A

Backscatter, β c(z) 20 - 30% 5 km 60 m Extinction, σc(z) within a factor of 2 for τ < 5 5 km 60 m Ice/water phase Layer by layer 5 km 60 m Effective emissivity, ε ±0.03 1 km N/A Ice particle size ±50% for ε > 0.2 1 km N/A Note: * assumes 30% uncertainty in the aerosol extinction-to-backscatter lidar ratio, Sa

2.3 Aerosols

Clouds and aerosols vary on different spatial and temporal scales and, thus, require different validation strategies. Aerosols typically have longer spatial correlation distances than clouds providing a greater opportunity for coincident comparisons between instruments. An exception to this rule is polar stratospheric clouds (PSCs), which, in most cases, have coincident distances much larger than tropospheric clouds and aerosols.

Aerosol height and thickness will be calculated from the attenuated aerosol backscatter coefficient. Comparisons are needed with similar or superior detection and ranging capabilities such as ground-based lidars or backscattersondes. Because aerosol height and thickness tends to remain fairly consistent over long distances, except near local sources (e. g. smoke stacks, fires, etc.), the coincident distances (50-100 km) between the CALIPSO ground track and validation site can be much larger than for clouds.

For CALIPSO, Level 2 aerosol optical depth and extinction products are retrieved from backscatter measurements. These parameters require validation of the data products and the assumptions used to calculate them; namely, the value of the extinction-to-backscatter ratio, Sa. A layer averaged Sa can be estimated by CALIPSO measurements and a density profile for elevated aerosol layers, but Sa is estimated using a variety of ancillary data for non-elevated layers. A large number of observations in the literature indicate that optical depth and extinction are much more variable than the aerosol layer properties of height and thickness and, therefore, require more stringent coincidence criteria (<50 km).

A high spectral resolution lidar, elevation-scanned backscatter lidar, or 532 nm Raman lidar would be extremely valuable for validating the extinction profile and selection of Sa in the retrieval algorithm. Unfortunately, few of these systems exist worldwide and fewer yet can resolve the boundary layer. A 355 nm Raman lidar would be helpful to validate the extinction profile at 532 and 1064 nm, but the extinction profile would need to be transferred from 355 nm. A backscatter lidar colocated with a sunphotometer would also be suitable to validate the extinction profile and Sa, though assumptions still need to be made to calculate these parameters and the layers would need to have a near-constant lidar ratio. A sunphotometer or multi-filter rotating spectroradiometer (MFRSR) would be useful to validate aerosol optical depth.

2.4 Clouds

Optical properties of clouds are usually more variable horizontally than layers of aerosols. Hogan and Illingworth (2000) find that for cirrus clouds, (the best case) matching errors by stations separated by 5 km were approximately 100% and for 1-2 km the matching error is 25-50%. Therefore, validation of cloud properties will largely rely on statistical techniques. Because correlation scales are small for cloud properties, particularly optical depth, sites with frequent long-term measurements that have many coincident measurements within a short distance will be given high priority. Cloud height and thickness is calculated in the same manner as for aerosol height and thickness and, therefore, requires such instruments as lidars or backscattersondes. Millimeter cloud radars will also be useful; but, because of the large difference in the detection sensitivities between lidars and radars, data from these instruments will be used in a more limited role for validation. The effect of multiple scattering on the determination of cirrus cloud height and thickness is expected to be small for the limited field of view of CALIPSO so that only attenuated backscatter is necessary to measure cloud height and thickness. These two parameters have the longest horizontal correlation scales for clouds (20-50 km) so that some direct comparisons may be made, particularly for non-convective clouds. Low clouds will be much more difficult to validate from the ground because for most low clouds the returned lidar signal for CALIPSO will be fully attenuated, so that it only cloud top is measured, while a ground lidar will be fully attenuated before reaching cloud top and measure only cloud base. A millimeter wavelength cloud radar may be more useful for these clouds. For nonattenuating low clouds, the effects of multiple scattering will be larger for the CALIPSO lidar and must be considered for all cloud data products.

Cloud optical depth, extinction profiles, and Sc are calculated similar to the analogous aerosol properties, but the correlation scales for clouds are quite small (< 5 km). Surface lidar sites can only be used where the clouds are overcast and uniform on scales similar to the distance between the surface site and the CALIPSO ground track. Only Raman and HSRL lidars can be used to validate cloud optical depth and extinction profiles, while for Sc a 532 or 1064 nm lidar must be present (a 355 nm Raman lidar alone will not suffice). Therefore, surface sites will play a small role in validating these cloud parameters.

Cloud ice/water phase is determined from the 532 nm depolarization ratio. Surface depolarization lidar at 532 nm is best, but a 355 nm depolarization lidar can be helpful, particularly for large particles (> 1 µm), where depolarization changes little with wavelength (Mishchenko et al., 1996). Correlation distances for cloud ice/water phase are larger than other cloud properties and the coincident distance (~ 50 km) may be large enough for direct comparisons.

2.5 IIR derived data products

Comparisons between the CALIPSO IIR and ground-based instruments are needed to support IIR calibration analysis and validation of its derived data products. Correlative measurements are needed along the satellite track that provide knowledge on the degree of cloudiness and altitude of cloud layers, profile information on temperature and humidity, and characterization of surface conditions such as temperature and emissivity. These measurements are needed for day and night satellite overpasses as well as over land and ocean with varying surface conditions.

To illustrate these requirements one can examine the IIR data product for effective emissivity, εc, of a cloud. This parameter is calculated from the relationship, εc = (Li - Lo)/(Lb - Lo), where Li is the upward radiance measured by the IIR, Lo is the radiance measured in a cloud free atmosphere, and Lb is the radiance from an opaque cloud at the same temperature. This latter term is obtained from temperature and humidity profiles for the cloud height determined from lidar observation. Comparisons with facilities that can independently reproduce this calculation and verify it with surface radiometers will be extremely valuable for evaluating the IIR emissivity product quality.

Cloud particle size is another data product that will be produced from the IIR. It is a challenging product to validate because it may vary considerably over short horizontal distances (< 1 km) and within thin vertical layers (< 300 m). Some sites, notably ARM sites, use a radar-IR or radar- lidar technique to produce particle size measurements. This technique would need to be validated by in-situ measurements of particle sizes before it may be used to directly validate CALIPSO particle size measurements. Effective emissivity and particle size will only be retrieved for thin cirrus and therefore validation will only focus on thin cirrus.

3. Existing Instrument Networks and Individual Sites

The following instrument networks and individual sites have been identified by the CALIPSO validation implementation team as being suitable for participating in validation activities and have been contacted for, or expressed interest in, participating in the QPQ validation program. Each network has a long history of measurements and a measurement and calibration protocol. For each network, a brief description of the network is given followed by a list of pertinent measurements and CALIPSO level II parameters that they validate.

3.1 Aeronet http://aeronet.gsfc.nasa.gov/

Aeronet is a federation of ground-based remote sensing aerosol networks, largely sunphotometers, around the world. Aerosol optical thickness at 1020, 870, 670, 500, 440, 380, and 240 nm are derived at most places. Sky radiance measurements along the solar alumcantar (i.e. at constant elevation angle with varied azimuth angles) and the solar principal plane (i.e. at constant azimuth angle with varied scattering angles) are made at 440, 670, 870, and 1020 nm to retrieve size distribution and phase function. Aerosol optical thickness is derived every 15 minutes or 0.25 air masses; whichever is more frequent, from an air mass of 7 in the morning to an air mass of 7 in the evening. Each measurement consists of a triplet of measurements at each wavelength that are analyzed for cloud screening and averaged. Sky radiance measurements are taken 6 times a day along the solar alumcantar and 9 times a day along the solar principal plane. Sun photometers are calibrated by the Langley method every 2-3 months, which is then transferred to field sunphotometers pre- and post-deployment to an accuracy of 1-2% for aerosol optical thickness, and every 9-12 months to get an accuracy of 5% for sky radiance.

The following measurements from the Aeronet sites listed in Section 7.1 would be suitable for CALIPSO validation (validated parameters in parentheses):

Sunphotometer (τa (532 nm), τa(1064 nm))

3.2 Asian Dust NETwork (AD-Net) http://info.nies.go.jp:8094/kosapub/index.html The AD-Net is an international virtual community, which was formed in February 2001. It was setup to provide rapid communication via the Internet on Asian dust events. The network observation of Asian dust was originally started in 1997 mainly with lidar groups in Japan. Since 1998, exchange of Asian dust information with lidar and other surface observations expanded to the East Asia countries of China and Korea. The AD-Net primary observation campaign take place every year in northern springtime from March 1 to May 31. Many of the lidars in the network belong to research programs on the atmospheric radiation and/or regional air-pollution, and the lidars are operated continuously throughout year.

Table 2 presents a list of instruments, the resolution in time and space of available lidar, and the CALIPSO Level II parameters validated for each site in the network.

Table 2: List of instruments, vertical range and resolution, time resolution, and parameters validated for each station within the AD-Net.

Station Instrument Lidar range Lidar time Validated parameter (resolution) resolution Beijing 532 nm 0.1-15 km (6 m) 15 mins. aerosol height/thickness, cloud w/polarization, height/thickness, β'(R, 532nm) /β'(R, 1064 nm lidar. ‖ 532nm)⊥ Cheju See MPLNET Chung-Li 532 nm, 1064 m 1- 30 km (24 m) aerosol height/thickness, cloud w/polarization lidar height/thickness, β'(R, 532nm)‖/β'(R,

532nm)⊥ Fukue 532 nm 0.1-15 km (6 m) 15 mins. aerosol height/thickness, cloud w/polarization, height/thickness, β'(R, 532nm) /β'(R, 1064 nm lidar. ‖ 532nm)⊥ Fukuyama 532 nm 0-15 km 15 mins. aerosol height/thickness, cloud w/polarization height/thickness, β'(R, 532nm) /β'(R, lidar. ‖ 532nm)⊥ Gwangju 355 nm, 532nm 0.5-30 km (7.5 10 mins. aerosol height/thickness, cloud

w/polarization, m) height/thickness, τa(532), σa(532), 1064 nm, 387 nm τa(1064), σa(1064), τc(532), σc(532), Raman lidar τc(1064), σc(1064), Sa (532), Sa (1064), Sc(532), Sc(1064), β'(R,

532nm)‖/β'(R, 532nm)⊥ Hedo 532 nm 0.1-18 km (6 m) 15 mins. aerosol height/thickness, cloud w/polarization, height/thickness, β'(R, 532nm)‖/β'(R, 1064 nm lidar. 532nm)⊥ Hefei 532 nm 0-18 km (30 m) Day and night aerosol height/thickness, cloud w/polarization, operation, 15 height/thickness, β'(R, 532nm)‖/β'(R, 1064 nm lidar. minute resolution 532nm)⊥ Hohhot 532 nm 0.1-15 km (6 m) 15 mins. aerosol height/thickness, cloud w/polarization lidar height/thickness, β'(R, 532nm)‖/β'(R,

532nm)⊥ Miyako-jima 532 w/polarization, 0.1-18 km (6 m) 15 mins. aerosol height/thickness, cloud 1064 nm lidars height/thickness, β'(R, 532nm)‖/β'(R,

532nm)⊥ Nagasaki 532 nm 0.1-18 km (6 m) 15 mins. aerosol height/thickness, cloud w/polarization, height/thickness, β'(R, 532nm)‖/β'(R, 1064 nm lidar 532nm)⊥ Nagoya 355, 532 troposphere and 5 mins. aerosol height/thickness, cloud

w/polarization, stratosphere (30 height/thickness, τa(532), σa(532), 1064 nm, and m) τa(1064), σa(1064), τc(532), σc(532), Raman lidar τc(1064), σc(1064), Sa (532), Sa (1064), Sc(532), Sc(1064), β'(R,

532nm)‖/β'(R, 532nm)⊥ Okayama 532 nm 0.1-15 km 15 mins. aerosol height/thickness, cloud w/polarization lidar height/thickness, β'(R, 532nm)‖/β'(R,

532nm)⊥ Sapporo 532 nm 0.1-18 km (6 m) 15 mins. aerosol height/thickness, cloud w/polarization, height/thickness, β'(R, 532nm) /β'(R, 1064 nm lidar ‖ 532nm)⊥ Sri Samrong 532 nm 0.1-18 km (6 m) 15 mins. aerosol height/thickness, cloud w/polarization, height/thickness, β'(R, 532nm) /β'(R, 1064 nm lidar ‖ 532nm)⊥ Suwon 532 nm 0.1-18 km (6 m) 15 mins. aerosol height/thickness, cloud w/polarization, height/thickness, β'(R, 532nm) /β'(R, 1064 nm lidar ‖ 532nm)⊥ Tokyo 355nm, 532 nm 0.1-15 km (7.5 5-10 min. aerosol height/thickness, cloud

w/polarization, m) height/thickness, τa(532), σa(532), 1064 nm, 387, 408, τa(1064), σa(1064), τc(532), σc(532), 607 nm Raman τc(1064), σc(1064), Sa (532), Sa lidar, sun (1064), Sc(532), Sc(1064), β'(R, photometer 532nm)‖/β'(R, 532nm)⊥ Toyama 532 nm 0.1-18 km (6 m) 15 mins. aerosol height/thickness, cloud w/polarization, height/thickness, β'(R, 532nm)‖/β'(R, 1064 nm lidar 532nm) Tsukuba 532 nm 0.1-15 km (6 m) 15 mins. aerosol height/thickness, cloud

w/polarization, height/thickness, τa(532), σa(532), 1064 nm lidar, 523 τa(1064), σa(1064), τc(532), σc(532), nm HSRL τc(1064), σc(1064), Sa (532), Sa (1064), Sc(532), Sc(1064), β'(R,

532nm)‖/β'(R, 532nm)⊥

3.3 Atmospheric Radiation Measurement (ARM) http://www.arm.gov/

The Atmospheric Radiation Measurement (ARM) Program is a multi-laboratory, interagency program that was created in 1989 with funding from the U.S. Department of Energy (DOE). The ARM Program is part of DOE's effort to resolve scientific uncertainties about global climate change with a specific focus on improving the performance of general circulation models (GCMs) used for climate research and prediction. These improved models will help scientists better understand the influences of human activities on the earth's climate. In pursuit of its goal, the ARM Program establishes and operates field research sites, called Cloud and Radiation Testbeds (CARTs), in several climatically significant locations. Scientists collect and analyze data obtained over extended periods of time from large arrays of instruments to study the effects and interactions of sunlight, radiant energy, and clouds on temperatures, weather, and climate. Sites include instruments to measure atmospheric profiles of aerosols and cloud optical properties, surface eddy flux, and surface meteorology. The instruments available for CALIPSO validation are discussed below and in Table 3.

The following measurements from the ARM sites would be suitable for CALIPSO validation and are summarized in Table 3 (validated parameters in parentheses):

Southern Great Plains (SGP) Central Facility (aerosol height/thickness, cloud height/thickness,

τa(532nm), τa(1064nm), σa(532), Sa(532), τc(532 nm), σc(532), Sc(532), β'(R, 532nm) ‖/β'(R, 532nm)⊥, ice particle size, ice cloud effective emissivity) Sunphotometer measurements at 1020 and 499 nm Multi-filter rotating shadowband radiometer at 500 nm Raman Lidar (runs day/night with 39 m range resolution) with 355 nm depolarization channel and a 387 nm Raman channel Ceilometer measurements at 905 nm Micro-pulse lidar at 523 nm mm-Wavelength cloud radar

The following instruments are also present but do not directly validate any CALIPSO parameters: condensation nuclei counter, optical particle counter (31 channels between 0.1-10 µm and one greater than 10 µm), ozone monitor, microwave radiometer (31.4 GHz), atmospheric emitted radiance interferometer (3-20 µm or 500-3300 cm-1, resolution 1 cm-1), radiosondes, 50 and 915 MHz Radar wind profiler/RASS, camera centered on zenith, whole sky imager (450 and 650 nm), narrow field of view sensor (869 nm, centered on zenith), absolute solar transmittance interferometer (1-5 µm or 2000-10000 cm-1, resolution 2 cm-1, pyranometer, pyrgeometer, pyrheliometer, uv-b radiometer, solar radiance transmission interferometer (620-1350, 1500- 2050, 2020-2550, 2420-3080, 3010-3830, 4020-4300 cm-1, 3 times a day), shortwave spectrometer, uv spectroradiometer, surface meteorological observing system (1 minute wind speed and direction, temperature, relative humidity, pressure, rain amount), temperature and humidity at 25 and 60 m, and a chilled mirror.

Southern Great Plains (SGP) Extended Facilities (sites listed in Section 7.1) (τa(532nm)) Multi-filter rotating shadowband radiometer for 500 nm

Also, a surface meteorological observing system (1 minute wind speed and direction, temperature, relative humidity, pressure, rain amount) is present.

Tropical Western Pacific (TWP) - Manus Island, Nauru Island, and Darwin (aerosol height/thickness, cloud height/thickness,τa(532nm), τa(1064nm), σa(532), Sa(532), ice particle size, ice cloud effective emissivity) Ceilometer at 905 nm Micropulse lidar at 523 nm mm-Wavelength cloud radar Sunphotometer at 1020 and 499 nm Multi-filter rotating shadowband radiometer at 500 nm

The following instruments are also present but do not directly validate any CALIPSO parameters: microwave radiometer (31.4 GHz), atmospheric emitted radiance interferometer (3- 20 µm or 500-3300 cm-1, resolution 1 cm-1), radiosondes, 915 MHz Radar wind profiler/RASS, whole sky imager (450 and 650 nm), absolute solar transmittance interferometer (1-5 µm or 2000-10000 cm-1, resolution 2 cm-1), pyranometer, pyrgeometer, pyrheliometer, uv-b radiometer, solar radiance transmission interferometer (620-1350, 1500-2050, 2020-2550, 2420-3080, 3010- 3830, 4020-4300 cm-1, 3 times a day), surface meteorological observing system (1 minute wind speed and direction, temperature, relative humidity, pressure, rain rate).

North Slope of Alaska - Barrow (aerosol height/thickness, cloud height/thickness, τa(532), σa(532), τa(1064), σa(1064), Sa (532), Sa (1064), τc(532), σc(532), Sc (532), τc(1064), σc(1064),

Sc (1064), β'(R, 532nm)‖/β'(R, 532nm)⊥, ice particle size, ice cloud effective emissivity) High spectral resolution lidar (HSRL) (100 m to 37.5 km with day/night operation) 532 nm w/depolarization and 1064 nm Ceilometer at 905 nm Micropulse lidar at 523 nm mm-Wavelength cloud radar Sunphotometer for 1020 and 499 nm Multi-filter rotating shadowband radiometer for 500 nm

The following instruments are also present but do not directly validate any CALIPSO parameters: microwave radiometer (31.4 GHz), atmospheric emitted radiance interferometer (3- 20 µm or 500-3300 cm-1, resolution 1 cm-1), radiosondes, 915 MHz Radar wind profiler/RASS, whole sky imager (450 and 650 nm), absolute solar transmittance interferometer (1-5 µm or 2000-10000 cm-1, resolution 2 cm-1), pyranometer, pyrgeometer, pyrheliometer, uv-b radiometer, solar radiance transmission interferometer (620-1350, 1500-2050, 2020-2550, 2420-3080, 3010- 3830, 4020-4300 cm-1, 3 times a day), wind speed and direction, temperature, relative humidity at 2, 10, 20, and 40 m and pressure, visibility, and precipitation at the ground.

North Slope of Alaska - Atqasuk (τa(532nm)) Multi-filter rotating shadowband radiometer for 500 nm

Table 3: Summary of instruments describe above at the various ARM sites.

Southern Great Southern Tropical North Slope of North Slope of Plains Central Great Plains Western Alaska Alaska Facility Extended Pacific (Barrow) (Atqasuk) Facilities Sun Photometer 1020 and 499 nm 1020 and 1020 and 499 nm 499 nm MFRSR 500 nm 500 nm 500 nm 500 nm 500 nm Raman Lidar 355 nm with polarization and 387 nm, both with 39 m vertical resolution Ceilometer 905 nm 905 nm 905 nm Micro-pulse Lidar 523 nm 523 nm 523 nm HSRL 532 nm with polarization, 1064 nm, both with 100 m vertical resolution and range to 37.5 km Mm wavelength Yes No Yes Yes No cloud radar Other instruments Yes (see text) Yes (see text) Yes (see Yes (see text) No not directly related text) to validation

3.4 Baseline Surface Radiation Network (BSRN) http://bsrn.ethz.ch/

BSRN is a project of the World Climate Research Programme (WCRP) aimed at detecting important changes in the earth's radiation field, which may cause climate changes. The objective of the BSRN is to provide, using a high sampling rate, observations of the best possible quality, for short and longwave surface radiation fluxes. These readings are taken from a small number of selected stations, in contrasting climatic zones, together with collocated surface and upper air meteorological data and other supporting observations.

The following measurements from the BSRN sites listed in Section 7.1 would be suitable for CALIPSO validation (validated parameters in parentheses):

Sunphotometer (τa (532 nm), τa(1064 nm))

Also all stations measure global, direct, and diffuse broadband solar radiation while most stations measure downward longwave, temperature, relative humidity, and pressure. Payerne, Von Neumayer, and Boulder measure upward shortwave and longwave irradiance and have radiosondes. Toravere and Tateno measure upward shortwave and longwave irradiance.

3.5 Climate Monitoring and Diagnostics Laboratory (CMDL) http://www.cmdl.noaa.gov/aerosol/

The CMDL of the National Oceanic and Atmospheric Administration (NOAA) conducts research related to the atmospheric constituents that are capable of forcing change in the climate of the earth or may deplete the ozone layer. Aerosol measurements began at the CMDL baseline observatories in the mid-1970s as part of the Geophysical Monitoring for Climate Change. The goal of this regional-scale monitoring program is to characterize means, variability, and trends of climate-forcing properties of different types of aerosols, and to understand the factors that control these properties.

The following measurements would be suitable for CALIPSO validation (validated parameters in parentheses):

Lidars at Mauna Loa Observatory and Boulder, Colorado are capable of measuring stratospheric and tropospheric aerosols and the height and thickness of cirrus clouds. A third lidar station at American Samoa will be operating. The lidars are restricted to nighttime measurements at 532 nm. The Mauna Loa Observatory lidar also measures 1064 nm aerosol scattering and water vapor in the troposphere using the Raman method. The lidars are permanently deployed and operated routinely. (Aerosol Height/Thickness, Cloud Height/Thickness)

3.6 Commonwealth of Independent States Lidar Network (CIS-LiNet) http://www.cis-linet.basnet.by/

CIS-LiNet (Commonwealth of Independent States Lidar Net) includes stationary and mobile lidar stations all over former USSR countries. CIS-LiNet was established in 2004 in the frame of the International Science and Technology Center (ISTC) Project. The net’s aims are regular measurements of aerosol and ozone vertical profiles to study their large-scale spatial and temporal transformations.

Table 4 presents a list of instruments, the resolution in time and space of any available lidar, and the CALIPSO Level II parameters validated for each site in the network.

Table 4: List of instruments, vertical range and resolution, time resolution, and parameters validated for each station within the CIS-LiNet.

Station Instrument Lidar range Lidar time Validated parameter (resolution) resolution Minsk Backscatter Lidar 2-30 km(64 m) 10 min aerosol height/thickness, cloud

1064, 532, 355 nm height/thickness, τa(532), w/polarization, σa(532), τa(1064), σa(1064), Sa CIMEL sunphotometer (532), Sa (1064), β'(R,

532nm)‖/β'(R, 532nm)⊥ Moscow Backscatter Lidar 532 aerosol height/thickness, cloud nm height/thickness Sergut Backscatter Lidar 532 0.5-30 km (15- 10-30 min aerosol height/thickness, cloud nm 300 m) height/thickness Teplokluchenka, Raman Lidar 532, 608 2-20 km(37 m) aerosol height/thickness, cloud

Kyrgyzstan nm height/thickness, τa(532), σa(532), τc(532), σc(532), Sa (532), Sc(532) Tomsk, Raman Lidar 308, 532 8-50 km(60 m) 15 mins. aerosol height/thickness, cloud

stationary nm, humidity, height/thickness, τa(532), temperature, Aerosol σa(532), τa(1064), Sa (532) Station, Standard Meteorological measurements, CIMEL sunphotometer Tomsk, mobile Raman Lidar 532 0,2-12 km (5-15 1-12 min. aerosol height/thickness, cloud

w/polarization, 608 m) height/thickness, τa(532), nm σa(532), τc(532), σc(532), Sa (532), Sc(532), β'(R,

532nm)‖/β'(R, 532nm)⊥ Vladivostok, Backscatter Lidar 532 2-20 km (60 m) 10-30 mins. aerosol height/thickness, cloud stationary nm height/thickness Vladivostok, Backscatter Lidar 532 1.5-15 km(60 10-30 min aerosol height/thickness, cloud mobile nm m) height/thickness shipboard Yakutsk Backscatter Lidar 532 3-50 km (30 m) 15-60 min aerosol height/thickness, cloud nm height/thickness

3.7 EARLINET http://www.earlinet.org/

EARLINET’s objective is to establish a quantitative comprehensive statistical database of the horizontal, vertical, and temporal distribution of aerosols on a continental scale. The goal is to provide aerosol data with unbiased sampling, for important selected processes, and air-mass history, together with comprehensive analyses of these data. The objectives will be reached by implementing a network of 21 stations distributed over most of Europe, using advanced quantitative laser remote sensing to directly measure the vertical distribution of aerosols, supported by a suite of more conventional observations. Special care will be taken to assure data quality, including intercomparisons at instrument and evaluation levels.

Table 5 presents a list of instruments, the resolution in time and space of any available lidar, and the CALIPSO Level II parameters validated for each site in the network.

Table 5: List of instruments, vertical range and resolution, time resolution, and parameters validated for each station within the EARLINET.

Station Instrument Lidar range Lidar time Data products (resolution) resolution available for validation Athens_EARLINET 355, 532, 387 nm lidar, 0.5-12 km 6 mins. aerosol meteorological data (15 m) extinction height/thickness, (P,T,U) only at night- cloud time height/thickness

τa(532), σa(532), Sa (532), τc(532), σc(532), Sc (532), ice cloud effective emissivity Barcelona_EARLINET 532,607, 1064 nm lidar, 0.25-10 km 1 min aerosol aerosol spectrometer, (7.5 m) height/thickness, pyranometer, cloud sunphotometer height/thickness

τa(532), σa(532), τa(1064), σa(1064), Sa (532), Sa (1064), τc(532), σc(532), Sc (532), τc(1064), σc(1064), Sc (1064) Bilthoven_EARLINET 355 nm and 532 nm 1-15 km (7.5 30 min. aerosol Raman lidar and 1064 nm m) height/thickness, backscatter lidar cloud height/thickness,

τa(532), σa(532), τa(1064), σa(1064), Sa (532), Sa (1064), τc(532), σc(532), Sc (532), τc(1064), σc(1064), Sc (1064) Cabaw_EARLINET 355, 532 w/depolarization, 1-5 km 5 min. aerosol 1064 nm Raman lidar, height/thickness, AERONET cloud sunphotometer, height/thickness,

Ceilometer, τa(532), σa(532), Radiosonde,10, 35, 95 τa(1064), σa(1064), GHz radar, and other Sa (532), Sa (1064), instrumentation available τc(532), σc(532), Sc (similar to ARM SGP site) (532), τc(1064), σc(1064), Sc (1064), β’(R,

355nm)‖/β’(R,

355nm)⊥, ice particle size, ice cloud effective emissivity Garmisch_EARLINET 355 nm, 532 nm, 1064 nm 0.2-10 km 10 s-3 min aerosol lidar (HSRL), visibility (3.75 m) extinction 532 height/thickness, meter, pyranometer, at daytime cloud spectrally resolved UV height/thickness

532 nm backscatter lidar 1.5-40 km 1-7 min τa(532), σa(532), (15 m/3.75 τa(1064), σa(1064), m) Sa (532), Sa (1064), τc(532), σc(532), Sc (532), τc(1064), σc(1064), Sc (1064) Hamburg_EARLINET 355, 387, 407, 532, 607, 0.3-10 km 10 s aerosol 1064 nm Raman lidar, (15 m) height/thickness, 355, 532nm pure cloud rotational Raman lidar, height/thickness,

1064 s+p-pol, and τa(532), σa(532), AERONET τa(1064), σa(1064), sunphotometer, ceilometer Sa (532), Sa (1064), τc(532), σc(532), Sc (532), τc(1064), σc(1064), Sc (1064), β’(R,

355nm)‖/β’(R, 355nm)⊥

Jungfraujoch_EARLINET 355, 387, 532, 607, 1064 4-11 km (7.5- 100 s aerosol nm w/polarization (355 300m m) height/thickness, nm); Raman lidars- Pure cloud rotational Raman at 532 height/thickness,

nm for temperature aerosol τa(532), σa(532), extinction/ backscatter τa(1064), σa(1064), measurement, Sa (532), Sa (1064), sunphotometer τc(532), σc(532), Sc (Meteoswiss), (532), τc(1064), σc(1064), Sc (1064), β’(R,

355nm)‖/β’(R,

355nm)⊥ L’Aquila_EARLINET 351nm, 382 nm, 393nm, .3-8 km a.g.l. 10 mins. aerosol 403nm Raman lidar, PTU (30 m) height/thickness, and PTO3 radiosonde cloud height/thickness, ice cloud effective emissivity Lecce_EARLINET 351, 383 w/ 0.4 - 7 km 3 mins. aerosol depolarization, 404 nm (1.5 m) extinction, height/thickness, Raman lidar, AERONET depolarization, cloud sunphotometer, meteo water vapor, height/thickness,

station (P, T, RH, wind), and τa(532), τa(1064), Vaisala radio sonde for temperature β'(R, 351nm) /β'(R, (P,T,RH) profiles at ‖ night-time 351nm)⊥ only Leipzig_EARLINET 355, 532 (polarization), 0.5 km - trop. 30 mins. (raw aerosol 1064, 387, 408, 529, for extinction 30 s) height/thickness, 530.2, 533.7, 535, and 607 and 0.1 - cloud nm Raman lidar, sun trop. for height/thickness,

photometer (380, 440, backscatter τa(532), σa(532), 500, 670, 870, 1020, and (60 m) τa(1064), σa(1064), 1640 nm), Vaisala radio Sa (532), Sa (1064), sonde (P, T, RH) τc(532), σc(532), Sc (532), τc(1064), σc(1064), Sc (1064), β’(R,

355nm)‖/β’(R,

355nm)⊥, ice cloud effective emissivity Minsk_EARLINET 355, 532, 1064 nm Lidar #1 5 (30) mins. aerosol and (lidar #2) height/thickness, 532 w/polarization lidars; 0.3(1)-10(30) cloud AERONET sunphotometer km height/thickness,

(15 m τa(532), σa(532), (128m)) τa(1064), σa(1064), Sa (532), Sa (1064),

β'(R, 532nm)‖/β'(R, 532nm)⊥

Munich_EARLINET 355, 387, 532, 607, 1064 0.2-5 km 0.1 s aerosol nm lidar (3.75 m) height/thickness, cloud height/thickness

τa(532), σa(532), τa(1064), σa(1064), Sa (532), Sa (1064), τc(532), σc(532), Sc (532), τc(1064), σc(1064), Sc (1064) Napoli_EARLINET 355, 387, 407, 532, 607 0.25-12 km 1 min. aerosol nm, Raman lidar, meteo. (15 m), 0.1-8 height/thickness, station (P,T,RH) Km (60m) cloud for WV height/thickness,

mixing ratio τa(532), σa(532), τa(1064), σa(1064), Sa (532), Sa (1064), τc(532), σc(532), Sc (532), τc(1064), σc(1064), Sc (1064), Neuchatel_EARLINET 532 nm w/polarization, 1-10 km (30 200-600 s aerosol meteo station m) height/thickness, cloud height/thickness,

β'(R, 532nm)‖/β'(R,

532nm)⊥ SIRTA_EARLINET See IPSL Network

OHP_EARLINET See IPSL Network Potenza_EARLINET 355, 387, 407, 532, 607, 0.5 km-a.l.s. 1 min. aerosol 1064 nm Raman lidar, – troposphere height/thickness, meteo station for extinction cloud (P,T,RH,winds), and 0.2 km height/thickness,

AERONETsunphotometer, a.l.s.- τa(532), σa(532), ceilometer, radiosonde, troposphere τa(1064), σa(1064), MW radiometer for Sa (532), Sa (1064), backscatter τc(532), σc(532), Sc (15 m) (532), τc(1064), σc(1064), Sc (1064), ice cloud effective emissivity Thessaloniki_EARLINET 355, 532, 387, 607 nm 0.8-12 km 5 mins. aerosol lidar, meteorological data (30 m) extinction height/thickness, (P,T,U) only at night- cloud AERONET sunphotometer time height/thickness

Brewer spectroradiometer τa(532), σa(532), τa(1064), Sa (532), 266, 289, 316 nm lidar, 0.7-8 km (7.5 4 mins. τc(532), σc(532), Sc spectral UV-B, meteo. m) (532) Station.

Belsk_EARLINET 694, 532, 1064 nm Trophosphere 2 min aerosol up to 8 km height/thickness, cloud Stratosphere 30 min height/thickness (night time) up to 30 km (15 m) Sofia_EARLINET 510.6 nm, 578 nm; Up to 7-8 km 1 min Aerosol 1 lasers with CuBr-vapor at daytime; height/thickness (We use only the ~15 - 20 km Cloud wavelength 510.6 nm) at night-time height/thickness Resolution: 15m or 30 m Madrid_EARLINET 532 nm lidar. 0.15-15 km 5 mins. aerosol aerosol spectrometer (6 m) height/thickness, (GRIMM 1108) cloud height/thickness

Granada_EARLINET 355, 387, 532, 607, 1064 0.25-12 km 1 min. aerosol nm Raman lidar, meteo (7.5 m) height/thickness, station (P,T,RH,winds), cloud AERONETsunphotometer, height/thickness,

Bentham DMc150 τa(532), σa(532), spectroradiometer, all sky τa(1064), σa(1064), camera, Multifilter Sa (532), Sa (1064), Rotating Shadowband τc(532), σc(532), Sc Radiometer, broadband (532), τc(1064), radiometers (Solar, UVB, σc(1064), Sc (1064) UVA, Thermal IR), TSI 3563 Integrating Nephelometer, Multi Angle Absorption Photometer, MAAP.

3.8 Institut Pierre Simon Laplace (IPSL) Lidar Network

IPSL operates five ground-based sites of interest to CALIPSO for validation purposes. Palaiseau (SIRTA), Haute Provence, and La Reunion Island are collaborating to define common algorithms. The macrophysics algorithm developed at SIRTA will be implemented at the other sites to retrieve cloud and aerosol layer detection, boundary layer height detection, cloud optical depth, and cloud ice/water discrimination. Further collaborations are in place to improve retrievals of aerosol optical properties using Raman channels.

Table 6 presents a list of instruments, the resolution in time and space of any available lidar, and the CALIPSO Level II parameters validated for each site in the network.

Table 6: List of instruments, vertical range and resolution, time resolution, and parameters validated for each station within the IPSL Lidar Network.

Station Instrument Lidar range Lidar time Validated parameter resolution (resolution)

Andoya 355 nm, 532 nm aerosol height/thickness, cloud

w/polarization, 1064 height/thickness, τa(532), σa(532), τc(532), nm lidar, 387 nm, 607 σc(532), τa(1064), σa(1064), τc(1064), nm Raman lidar σc(1064), Sa (532), Sc (532), Sa (1064),

Sc(1064), β'(R, 532nm)‖/β'(R, 532nm)⊥ Dumont 532 nm w/polarization, Stratosphere aerosol height/thickness, cloud

d'Urville 1064 nm lidar, 607 height/thickness, τa(532), σa(532), τc(532), Raman lidar σc(532), τa(1064), σa(1064), τc(1064), σc(1064), Sa (532), Sc (532), Sa (1064), Sc(1064), β'(R,

532nm)‖/β'(R, 532nm)⊥ Haute 532 nm lidar, 607 nm Troposphere aerosol height/thickness, cloud

Provence Raman lidar and height/thickness, τa(532), σa(532), τc(532), stratosphere σc(532), Sa (532), Sc(532) La 532 nm with Troposphere aerosol height/thickness, cloud

Reunion polarization, 1064 nm and height/thickness, τa(532), σa(532), τc(532), Island lidar, 607 Raman stratosphere σc(532), τa(1064), σa(1064), τc(1064), lidar σc(1064), Sa (532), Sc (532), Sa (1064),

Sc(1064), β'(R, 532nm)‖/β'(R, 532nm)⊥ Palaiseau 532 nm 0.5-15 km 10 s aerosol height/thickness, cloud

w/polarization, 1064 (15 m) height/thickness, τa(532), σa(532), τa(1064), nm lidar, CIMEL σa(1064), Sa (532), Sa (1064), β'(R, sunphotometer, 94 532nm) /β'(R, 532nm) ice particle size GHz radar ‖ ⊥,

3.9 Micro-Pulse Lidar Network (MPLNET) http://mplnet.gsfc.nasa.gov/

MPLNET is a worldwide network of micro-pulse lidar (MPL) systems. MPLNET is run by the members of the Cloud and Aerosol Lidar Group in Code 912 at GSFC and is funded by NASA’s EOS program. The MPL is a single channel (523 nm), autonomous, eye-safe lidar system originally developed at GSFC and now commercially available. The MPL is used to determine the vertical structure of clouds and aerosols with a 30 - 300 m vertical resolution up to 20 km. The MPL data are analyzed to produce optical properties such as extinction and optical depth profiles of clouds and aerosols. The primary goal of MPLNET is to provide long-term data sets of cloud and aerosol vertical distributions at key sites around the world. The long-term data sets will be used to validate and help improve global and regional climate models, and also serve as ground-truth sites for NASA/EOS satellite programs.

The following measurements from the MPLNET sites listed in Section 7.1 would be suitable for CALIPSO validation (validated parameter in parentheses):

Micro-pulse lidar at 523 nm (aerosol height/thickness and cloud height/thickness)

3.10 Network for the Detection of Stratospheric Change (NDSC) http://www.ndsc.ncep.noaa.gov/

The NDSC is a set of remote sounding research stations for observing and understanding the physical and chemical state of the stratosphere. NDSC began network operations in January 1991. Several international sites are actively taking measurements of the following: aerosol, ozone, and temperature via lidars; ozone, temperature, and relative humidity sondes; and FTIR for measuring HCl, HF, CH4, C2H6, C2H2, N2O, O3, CO, CHF2Cl, HCN, HNO3, CLONO2, NO, and NO2.

Table 7 presents a list of instruments, the resolution in time and space of any available lidar, and the CALIPSO Level II parameters validated for each site in the network.

Table 7: List of instruments, vertical range and resolution, time resolution, and parameters validated for each station within the NDSC.

Station Instrument Lidar range Lidar time Validated parameter (resolution) resolution Andoya See IPSL Lidar Network Dumont See IPSL Lidar d'Urville Network Garmisch lidar aerosol height/thickness, cloud height/thickness GSFC See REALM

Haute See IPSL Lidar Provence Network Lauder Lidar, 6-36 km aerosol height/thickness, cloud backscattersonde height/thickness Mauna Loa See CMDL McMurdo Lidar, Nighttime only aerosol height/thickness, cloud backscattersonde height/thickness Ny Alesund 355, 532, 1064 nm 10-40 km (7.5 aerosol height/thickness, cloud

Lidar, nepholometer, m) height/thickness, τa(532), σa(532), sunphotometer, in- τa(1064), σa(1064), Sa (532), Sa situ aerosol (1064), ice cloud effective emissivity measurements, backscattersonde, radiosondes Okinawa Lidar aerosol height/thickness, cloud height/thickness Poker Flats 532 nm aerosol height/thickness, cloud w/polarization lidar height/thickness, β'(R, 532nm)‖/β'(R,

532nm)⊥ La Reunion See IPSL Lidar Island Network Suwon See AD-Net Table lidar aerosol height/thickness, cloud Mountain height/thickness Thule lidar Day and night aerosol height/thickness, cloud height/thickness Toronto lidar Day and night aerosol height/thickness, cloud height/thickness

Several other sites have backscattersondes only and are listed in Section 7.1.

3.11 Regional East Atmospheric Lidar Mesonet (REALM)

REALM is a proposed loose confederation of lidar sites building on the research capabilities already established at a number of Eastern North America lidar facilities. Lidar systems in REALM are expected to deliver (at minimum) lidar backscatter ratio at the fundamental or one of the harmonics of the Nd:YAG laser.

Table 8 presents a list of instruments, the resolution in time and space of any available lidar, and the CALIPSO Level II parameters validated for each site in the network.

Table 8: List of instruments, vertical range and resolution, time resolution, and parameters validated for each station within the REALM.

Station Instrument Lidar range Lidar time Validated parameter (resolution) resolution CCNY 355 nm, 532 nm, aerosol height/thickness, cloud and 1064 nm lidar height/thickness, Dalhousie 532 nm aerosol height/thickness, cloud University w/polarization height/thickness, β'(R, 532nm)‖/β'(R,

532nm)⊥ Ground- 532 nm lidar aerosol height/thickness, cloud winds height/thickness GSFC 355 nm, 532 nm aerosol height/thickness, cloud

w/polarization, and height/thickness, τa(532), σa(532), 1064 w/ τc(532), σc(532), τa(1064), σa(1064), polarization lidar, τc(1064), σc(1064), Sa (532), Sc 387 nm and 607 (532), Sa (1064), Sc(1064), β'(R, Raman lidar 532nm)‖/β'(R, 532nm)⊥ Hampton 532 and 1064 nm aerosol height/thickness, cloud University lidar height/thickness Howard 532 nm lidar aerosol height/thickness, cloud University height/thickness MSC 532 nm and 1064 (3.75 m) 1 minute aerosol height/thickness, cloud nm lidar height/thickness Penn State 355 nm and 532 0-10 km aerosol height/thickness, cloud University nm lidar height/thickness UAH 532 nm and 1064 aerosol height/thickness, cloud nm lidar height/thickness UMBC 355 nm, 532 nm aerosol height/thickness, cloud

w/polarization, height/thickness, τa(532), σa(532), and1064 τc(532), σc(532), τa(1064), σa(1064), w/polarization τc(1064), σc(1064), Sa (532), Sc lidar, 387 nm and (532), Sa (1064), Sc(1064), β'(R, 607 Raman lidar 532nm)‖/β'(R, 532nm)⊥

3.12 USDA MFRSR network http://uvb.nrel.colostate.edu/UVB/home_page.html http://hog.asrc.cestm.albany.edu/

The USDA UVB Radiation Monitoring Program is a program of the US Department of Agriculture's Cooperative State Research, Education and Extension Service (CSREES). The program was initiated in 1992, through a grant to Colorado State University, to provide information on the geographical distribution and temporal trends of UVB (ultraviolet -B) radiation in the United States. This information is critical to the assessment of the potential impacts of increasing ultraviolet radiation levels on agricultural crops and forests.

The following measurements from the USDA MFRSR sites listed in Section 7.1 would be suitable for CALIPSO validation (validated parameter in parentheses):

Multi-filter rotating shadowband radiometer (τa(532nm))

The following instruments are also present at USDA sites, but do not directly validate any CALIPSO parameters: downward looking photometer, broadband uv-b pyranometer (280-330 nm), UV MFRSR (300, 305.5, 311.4, 317.6, 325.4, 332.4, and 368 nm), and instruments to measure temperature and humidity.

3.13 Individual Sites

Several investigators interested in participating in the QPQ validation program have provided the details, summarized in Table 9 of their proposed measurements that would be suitable for CALIPSO validation.

Table 9: Instruments and locations of several sites not affiliated with any instrumented networks.

Site Investigators Lat(°) Lon(°) Alt(m) Instruments Buenos Eduardo Quel -34.55 -58.50 15 355, 532, 1064 nm backscatter lidar (300 m- Aires_Quel 10 km), a Raman lidar observing backscatter at 308, a Raman N2 channel at 332 nm, and a sunphotometer. Buenos Mario -34.6 -58.5 15 532 nm with polarization, 1064 nm Aires_Lavorato Lavorato backscatter lidar (70 m-22 km, 20 s time resolution), radiosonde, and an Aeronet sunphotometer. City U. of Hong Andrew Cheng 22.34 114.17 44 532 nm lidar, 0.1-8 km range (7.5m Kong resolution), 1 min. time resolution. Also similar mobile lidar with 5-15 min. time resolution. Sunphotometer is also available at the stationary location. Davis Station Andrew -68.58 77.97 532 nm HSRL with polarization minimum Klekociuk altitude at 5-20 km Dome-C Vito Vitale -75.10 123.29 3200 532 nm w/polarization, 1064 nm lidar, sunphotometer Hohenheim, Andreas 48.7 9.2 532 nm and 1064 nm Backscatter Lidar (3m Germany Behrendt and 0.03 s resolution, day/night) and 355 nm Raman Lidar (0.03 s resolution) Jabiru Ross Mitchell -12.66 132.8 30 sunphotometer Kototabang, Chikao -0.2 100.3 532 nm Raman Lidar with depolarization Indonesia Nagasawa (100m resolution) Lake Argyle Ross -16.11 128.75 150 sunphotometer Mitchell Ny Alesund Cristoph Ritter 78.92 11.93 7 355, 387, 407, 532 w/depolarization, 607, 1064 nm Raman Lidar, and sunphotometer Potenza, Italy Paolo Di 40.64 15.85 770 Raman Lidar 355 nm with polarization, Girolamo 387, 532 nm (0-30 km) Pune, India Panuganti 18.53 73.85 559 514.5 nm lidar with depolarization, Devara sunphotometer Qingdao, China Xiaoquan 36.07 120.33 Micro Pulse Lidar at 532 nm 1 hour time Song resolution Quebec, Canada Luc 46.88 -71.47 532 and 1064 nm backscatter lidar with Bissonnette polarization (0.2-3 km range) measuring mainly lower cloud properties. Quito Alan Robock 0.00 lidar Rio Gallegos Eduardo Quel -51.92 -69.23 0 355, 532, 1064 nm backscatter lidar and sunphotometer. Also water vapor and ozone lidar. Rome, Italy Gian 41.84 -12.65 130 532 nm backscatter lidar with polarization Paolo Gobbi (0.2-14 km day range, 0.2-20 km night range, 6 min. resolution) and CIMEL sunphotometer. Sao Paulo Eduardo -23.56 -46.74 532 nm lidar (0-30 km night range, 0-12 km Landulfo day range), CIMEL sunphotometer Shigaraki, Japan Takuji 34.9 136.1 532 nm Raman lidar (9 m 10 s resolution Nakamura night only, backscatter data products day/night) Tinga Tingana Ross -28.98 139.99 50 sunphotometer Mitchell Trivandrum, M 8.55 76.96 6 355, 532 w/depolarization, 1064 nm lidar. India Satyanarayana Can also run Raman channels. Zanjan, Iran Hamid 36.67 48.48 532 nm backscatter lidar Khalesifard NOAA/ETL Janet Intrieri Mobile 523 nm lidar with polarization Natal, Brazil James Rosen backscattersondes Cruises in the Michael Cloud Particle Imager on a tethered balloon northern part of Kahnert and the Atlantic Jakob Stamnes Ocean, and campaigns on Svalbard (Spitsbergen)

4. Coverage of Various Aerosol and Cloud Regions

When the distance between the CALIPSO ground-track and a ground site is within a threshold distance that event is called a coincident observation. Section 7.2 in the appendix shows a table of the expected number of coincident observations during 16 days of orbits for validation sites at every 10 degrees of latitude for several separation distances between the CALIPSO ground-track and a validation site. For the validation network to be effective, however, it must cover various different aerosol and cloud regions. Validation of aerosol and cloud parameters should be distributed to allow validation of these parameters for a variety of aerosol and cloud types.

4.1 Aerosols

Aerosol types and the sites that observe those types are included in Table 10. Height, thickness, and optical depth have complete coverage of all aerosol types. Extinction profiles and the information needed to calculate the extinction-to-backscatter ratio do not have nearly as many sites. However, the coverage is similar to the height/thickness parameter with the exception of the lack of any sites in China for the extinction coefficient and Sa.

Table 10: Aerosol types and regions and the sites that sample those aerosols

Aerosol Type Height/Thickness τa σa Sa Urban/polluted Eastern U.S. Several REALM sites, Several Aeronet sites GSFC, UMBC GSFC, UMBC COVE Several MFRSR sites Central Europe Several Earlinet, IPSL, Several Aeronet sites Several Several and NDSC sites, Rome, Several BSRN sites Earlinet sites, Earlinet sites, Potenza Several Earlinet sites, Haute Haute Haute Provence, Provence, Provence Palaiseau Palaiseau Palaiseau China Several AD-NET sites, Several Aeronet sites, Hong Kong Hong Kong Hong Kong, Qingdao Hong Kong India/Indian Pune, Reunion Island, Male, Kanpur, Pune, Pune, Reunion Pune, Reunion Ocean Maldives Reunion Island Island Island Biomass burning South America Buenos Aires, Sao Several Aeronet Sites Buenos Aires Buenos Aires Paulo Southern Africa Reunion Island Several Aeronet Sites Reunion Island Reunion Island Indonesia Darwin, Kototabang Darwin, Kototabang Darwin, Darwin, Kototabang Kototabang Desert dust Saharan Several Earlinet sites, Dakar, Several Earlinet Several Several Dakar Sites Earlinet sites Earlinet Sites Asian Several AD-Net sites, Several Aeronet sites Gwangju, Gwangju, Hong Kong, Qingdao Tokyo, Tokyo, Tsukuba Tsukuba Polluted marine Aberystwyth, COVE, COVE, Okinawa, Aberystwyth, Palaiseau (sea salt, sulfate, Lisbon, Napoli, Palaiseau Palaiseau soot) Okinawa, Palaiseau, Rome, Monterey Dusty marine (sea Napoli, Suwon, Azores, Capo Verde, Suwon Suwon salt, sulfate, dust) Nagasaki, Dakar Bermuda Clean Continental SGP, Haute Provence Several Aeronet Sites SGP, Haute SGP, Haute Several ARM sites, Provence Provence Haute Provence Clean Marine (sea American Samoa, Manus, Nauru, Hilo, Manus, Manus, Nauru, salt) Manus, Nauru, Mauna Mauna Loa, Tahiti, Nauru, Mauna Loa Loa, Barbados, Kwajalein, Roosevelt Mauna Loa Maldives Roads Arctic haze Andoya, Barrow, Ny Andoya, Barrow, Andoya, Andoya, Alesund Atqasuk, Ny Alesund Barrow, Ny Barrow, Ny Alesund Alesund

4.2 Clouds

Cloud types and the sites that observe those types are included in Table 11. The height/thickness parameter has sites for all cloud types and the phase parameter is missing only tropical cloudy and Mediterranean sites. The coverage for Sc, τc, and σc are not as good as the coverage for aerosols because the sites with sunphotometers can no longer be used to measure or constrain the calculation of these parameters for clouds. Only twelve sites can validate τc and σc, and only nine sites can validate Sc.

Table 11: Cloud types and the sites that sample those clouds

Cloud Type Height/Thickness τc and σc Sc Phase Tropical cloudy American Samoa, Kototabang Kototabang Kototabang Barbados, Dakar, Darwin, Kototabang, Maldives, Manus, Nauru Desert marine Dakar, Suwon, Suwon, Nagasaki Nagasaki Subtropical • land Gwangju, Hefei, Sri Gwangju Gwangju Gwangju, Samrong, Hefei, Sri Samrong • ocean Mauna Loa, Reunion Reunion Island Reunion Island Reunion Island Island Mediterranean Several EARLINET Potenza Potenza Potenza sites, Haute Provence, Rome Mid to high latitude • land Several AD-Net sites, Cabauw, Cabauw, Several AD- SGP, Several CIS- Kuhlungsborn, Kuhlungsborn, NET sites, LiNET sites, Several Leipzig, Leipzig, Several EARLINET sites, Teplokluchenka, Teplokluchenka, EARLINET Several NDSC sites, Tomsk Tomsk sites, Minsk, Several REALM sites Tomsk • ocean Aberystwyth, Cove, Aberystwyth Aberystwyth Suwon Suwon, Lisbon Polar troposphere • Antarctic Dome Concordia, Dumont d' Urville Dumont d' Dome Dumont d' Urville, Urville Concordia, McMurdo, Syowa Dumont d' Urville • Arctic Andoya, Barrow, Ny Andoya, Barrow Andoya, Barrow Andoya, Alesund Barrow PSCs • Antarctic Davis Station, Dome Davis Station, Davis Station, Davis Station, Concordia, Dumont d' Dumont d' Urville Dumont Dome Urville, McMurdo, d'Urville Concordia, Syowa Dumont d'Urville • Arctic Barrow, Several NDSC Andoya, Barrow Andoya, Barrow Andoya, Poker sites Flats

5. Implementation

Dr. Thomas A. Kovacs will lead the CALIPSO QPQ validation effort with support from Dr. M. Patrick McCormick (CALIPSO Co-Principal Investigator). The CALIPSO QPQ validation implementation team will work closely with the CALIPSO mission validation team led by Dr. Charles R. Trepte of NASA LaRC to make sure that the QPQ activities are consistent and collaborative with the overall mission validation. Dr. Kovacs will serve as the point of contact for coordination of the QPQ validation sites. He will also obtain, transfer, and catalog all data from these sites for validation studies, and provide data storage for validation sites without accessible storage and for data requested by the CALIPSO PI.

A schedule of the milestones for implementing the QPQ validation plan is given below. A protocol for the free exchange of data will be included in a follow-up letter to responders to the QPQ validation announcement letters and is included in the appendix in Section 7.3.

5.1 The QPQ validation milestones

2001 Submitted QPQ validation plan draft - Oct.

2002 Submitted final draft of the QPQ validation plan - June Sent QPQ validation announcement letter – June Set up initial QPQ validation website at http://calipsovalidation.hamptonu.edu – October

2003 Complete coincident statistics for main sites - July Data exchange protocols developed for approval - November

2004 Order server and QPQ validation storage media - March Send follow up letters to announcement responders - April

2005 Set up ftp server web site, data storage, and catalog in coordination with LaRC ≥ L - 4 months Send out password access to the data catalog ≥ L - 4 months Store selected data, update data catalog, and continue validation studies - Post launch Continue communication of coincidence and orbital path with QPQ validation sites and campaigns - Post launch Validation data should begin to be gathered - L + 40 days Obtain level IIa validation data for preliminary data validation ≤ L + 135 days Complete preliminary validation studies on level IIa data within the first 135 days of launch ≤ L + 135 days Workshop on Level 1 and Level 2a data products approximately L + 4 months

2006 Workshop on comprehensive data comparison approximately L + 15 months

5.2 Communications with Sites

In 2003, coincident statistics were completed for all interested sites and networks. NASA LaRC will propagate the latest CALIPSO orbital predicts for 16 days using STK and supply HU with the coincident statistics for the QPQ validation sites that HU will provide. These statistics will be uploaded to the QPQ validation website weekly after launch and is available on the QPQ validation website. The data exchange protocol (Section 7.3) is complete and uploaded to the same website. A follow-up letter was sent to provide the interested sites with important information related to the QPQ validation plan and to verify and gather further information including: type of instruments, calibration protocol, archival protocol, observational protocol (times, altitudes, etc.), and aerosol types typically observed at each site that the point of contact manages. In order to keep the communication to a manageable level only top-level network administrators will be contacted for networked sites.

5.3 Data Exchange, Storage, and Handling

The data storage system will be procured and set up at Hampton University. This storage system will involve and require a server/workstation, archival tapes, and a data manager specialist. The workstation/server will be set up as an ftp server to obtain and disseminate data and will need software for validation data analysis. The ftp server will be accessible to the CALIPSO science team, the QPQ validation implementation team, and the PIs of the validation sites for as long as the PI requests. Sites that utilize a network data archive will be expected to update the validation implementation team on the availability of data of interest to the CALIPSO science and validation implementation teams. These network websites must provide adequate data access for the CALIPSO science and validation implementation teams. A listing of these specific sources and resources needed to utilize the data will be prepared as part of a data catalog and will include URLs, point of contact, email addresses, access instructions, data format, etc. The data catalog will update data available at these sites and from the HU server so that any interested investigator knows what data are available for validation. The data providers will supply this information each time they upload CALIPSO validation data to a data archive. Any network that does not have an existing archive must upload their data to HU's data storage to insure that all interested parties have access to validation data when needed.

The data manager specialist is responsible for making sure that data provided by a validation site is readable and conforms to any prearranged data format. This person will then put the data onto an ftp site where the science and validation implementation teams and the individual data PIs will have read-only access via a password. If data do not conform to the prearranged data format, decided by the validation implementation team, it will be stored in a separate folder. It is up to the data providers to periodically check that their data are being placed in the correct folder. For security purposes anybody who wants to upload or download data must supply an IP address for the machine that they will use to transfer the data. The data manager will move data to an archive tape when the ftp site becomes full and replace data on the ftp site for a short period of time when requests for archived data are received. This person will also backup the data and insure the data are secure from outside manipulation.

In 2005, the ftp server web site, data storage, and catalog in coordination with LaRC will be set- up and fully tested before launch. All data exchange protocols will be agreed upon and signed electronically when a validation team member logs into the data catalog. Orbital predicts and coincident statistics will be updated on the website on a regular basis, a month or so before launch, then routinely after launch at reasonable intervals. These statistics will provide sites with times of satellite overpasses. The orbital predicts will provide mobile sites with locations and times of the CALIPSO overpasses so that they may plan to position their instruments appropriately. Also, we will attempt to involve new sites as they become available/discovered, tempered with needs and our judgment of quality.

Storing of validation data will begin at the request of the CALIPSO PI. During the first 135 days after launch, studies will be performed to preliminarily validate level 2a data before the data are released to the public. QPQ validation is critical at this time as it may be the only source of validation data. Sites identified by the science and validation implementation teams will be contacted to arrange for a timely data exchange within a short time after observations are made.

If at any time during the validation period, an event deemed significant by the CALIPSO science team, such as a volcanic eruption, should take place, the QPQ validation program will be critical in validating the calibration and algorithms for the CALIPSO mission. For example, during a major volcanic eruption, sites that monitor the stratosphere will become especially important and validation studies with these sites will take priority. For an eruption that causes the atmosphere to become optically thick, special care will be given to increased errors in the tropospheric aerosol measurements due to transmission losses. Calibration, which is done by normalization with a clear region of the stratosphere could be affected if aerosols reach altitudes used for normalization by CALIPSO. Ground based measurements will be used to monitor the aerosol loading in these assumed clear regions.

After launch the HU validation implementation team will begin conducting validation studies consistent with the approach described in Section 2.1 and the data exchange protocol. In the first 135 days after launch, HU will assist in conducting preliminary validation studies. Because of HU's involvement and expertise in stratospheric aerosol and cloud studies, validation studies in this area will be a focus and will involve a graduate student. HU will also be involved in validation studies during significant events as describe above because of their involvement in coordinating validation sites during these events. Other studies will be initiated as the QPQ validation program matures.

6. References

Hogan, R. J., and A. J. Illingworth, "Deriving cloud overlap statistics from radar, Quart. J. Roy. Meteorol. Soc., 126(569A), 2903-2909 (2000).

Mishchenko, M., L. Travis, and A. Macke, “Scattering of light by polydisperse, randomly oriented, finite circular cylinders”, Applied Optics, 35, 4927-4940 (1996). 7. Appendix

7.1 Latitude, Longitude, and Altitude of all QPQ validation sites. Sites are listed under each network. Some sites are listed under multiple networks.

Station Name Lat. Long. Alt. Station Name Lat. Long. Alt.

AD-Net ARM

Beijing 39.90 116.30 100 Ashton_KS 37.13 -97.27 * CheJu 33.00 126.00 * Atqasuk_AK 70.47 -157.41 * Chung-Li 25.00 121.00 * Barrow_AK 71.27 -156.83 * Fukue 32.63 128.83 * Byron_OK 36.88 -98.29 * Fukuyama 34.47 133.23 * Christmas_Island 1.87 -157.33 * Gwangju 35.10 126.53 * Coldwater_KS 37.33 -99.31 * Hedo 26.90 128.30 * Cordell_OK 35.35 -98.98 * Hefei 31.90 117.16 * Cyril_OK 34.88 -98.21 * Hohhot 40.94 111.37 * Darwin -12.46 130.93 * Miyakojima 24.70 125.30 * El_Reno_OK 35.56 -98.02 * Nagasaki 32.78 129.86 * Elk_Falls_KS 37.38 -96.18 * Nagoya 35.10 137.00 * Halstead_KS 38.11 -97.51 * Okayama 34.41 133.57 * Hillsboro_KS 38.31 -97.30 * Sapporo 43.10 141.30 * Lamont_OK_ARM 36.61 -97.49 * Sri_Samrong 17.15 99.95 * Larned_KS 38.20 -99.32 * Suwon 37.14 127.04 * LeRoy_KS 38.20 -95.60 * Tokyo 35.66 139.80 * Manus -2.06 147.43 * Toyama 36.70 137.10 * Meeker_OK 35.56 -96.99 * Tsukuba 36.05 140.12 * Morris_OK 35.69 -95.86 * Nauru_ARM -0.52 166.90 * Aeronet Okmulgee_OK 35.62 -96.07 * Pawhuska_OK 36.84 -96.43 * Abracos -10.75 -62.35 200 Plevna_OK 37.95 -98.33 * Aguascalientes 21.70 -102.32 2000 Ringwood_OK 36.43 -98.28 * Aguas_Emendadas -15.58 -47.66 1100 Seminole_OK 35.25 -96.74 * Aire_Adour 43.70 0.25 80 Southern_Great_Plains 36.60 -97.50 * Albuquerque 35.05 -106.54 1645 Towanda_KS 37.84 -97.02 * Al_Dhafra 24.25 54.53 40 Tyro_KS 37.07 -95.79 * Alta_Floresta -9.92 -56.02 175 Vici_OK 36.06 -99.13 * Andros_Island 24.70 -77.80 0 Angiola 35.93 -119.53 210 BSRN Anmyon 36.52 126.32 47 Arica -18.46 -70.30 25 Alice_Springs_Australia -23.70 133.87 547 Ariquiums -9.92 -63.03 80 Bermuda_BSRN 32.37 -64.33 8 Ascension_Island -7.97 -14.40 30 Billings_ARM_CART 36.60 -97.49 317 Avignon 43.91 4.86 32 Carpetras_France 44.05 5.05 100 Azores 38.53 -28.62 50 Florianapolis_Brazil -27.58 -48.48 11 Babina -1.91 -59.48 80 Ibrin_Nigeria 8.53 4.57 350 Bahrain 26.31 50.50 0 Kwajalein_Marshall_Islan 8.72 167.73 10 Banizoumbou 13.53 2.65 250 Lindenberg_Germany 52.22 14.12 125 Barbados 13.17 -59.50 0 Ny_Alesund_BSRN 78.93 11.93 11 Barrow 71.31 -156.67 0 Payerne_Switz 46.82 6.93 491 Barnaul 53.00 83.00 0 Regina_CA 50.20 -104.28 578 Beijing 39.78 116.58 100 Syowa_Base_Antarctica -69.00 39.58 18 Belterra -2.63 -54.95 70 Taterno_Japan 36.05 140.13 25 Ben_McDhui -30.71 27.62 2450 Toravere_Obs_Estonia 58.33 26.47 70 Bermuda_Aeronet 32.37 -64.68 10 VonNeumayer_Antarctica -70.65 -8.25 42 Bethlehem -28.25 28.33 1709 Biarritz 43.48 -1.55 0 CIS-LiNet Big_Meadows 38.52 -78.44 1082 Billerica 42.52 -71.25 0 Minsk 53.90 27.38 * Bonanza_Creek 64.73 -148.30 150 Moscow 55.00 37.00 * Bondoukoui 11.85 -3.75 0 Sergut 61.2 73.5 * Bondville 40.05 -88.37 212 Teplokluchenka 42.50 78.40 * Bordeaux 44.78 -0.57 40 Tomsk 56.50 85.00 * Bragansa -0.83 -46.63 55 Vladivostok 43.00 131.90 * Brasilia -15.92 -47.90 1100 Yakutsk 61.40 129.30 * Bratts_Lake 50.26 -104.70 586 BSRN_BAO_Boulder 40.03 -105.00 1604 CMDL Bucarest 44.45 26.52 44 Buena_Vista 35.22 -119.26 0 American_Samoa -14.23 170.56 * Burtonsville 39.10 -76.94 50 Boulder_Colorado 40.03 -105.00 1604 Campo_Grande -20.45 -54.62 500 Mauna_Loa_Observatory 19.54 -155.58 3397 Capoverde 16.72 -22.93 60 Carlsbad 32.37 -104.23 942 EARLINET Cartel 45.37 -71.92 300 Cart_Site 36.60 -97.40 315 Athens 37.90 23.60 111 CCNY 0.05 -73.95 100 Barcelona 41.39 2.12 * CEILAP_BA -34.57 -58.50 10 Belsk 51.80 20.80 190 Che_Ju 33.00 126.00 0 Bilthoven 52.12 5.20 5 Chequamegon 45.92 -90.25 0 Cabauw 51.97 4.93 1 China_Lake 35.67 -117.75 800 Garmisch 47.60 11.06 730 Chinhae 35.16 128.65 69 Granada 37.16 -3.60 680 Churchill 58.73 -93.82 10 Hamburg 53.57 9.97 * Clermont_Ferrand 45.76 2.96 1464 Haute Provence 43.93 5..70 590 Cocunut_Island 21.41 -157.78 0 Jungfraujoch 46.55 7.98 3580 Coleambally -34.81 146.06 127 LAquila_Italy 42.35 13.38 683 Columbia_SC 34.02 -81.04 95 Leece_Italy 40.33 18.10 * Concepcion -16.13 -62.02 500 Leipzig 51.35 12.43 * Cordoba_CETT -31.52 -64.45 730 Madrid 40.27 -3.43 * COVE 36.88 -75.70 0 Minsk_Belarus 53.92 27.60 * Creteil 48.78 2.43 57 Munich 48.15 11.57 * CUIABA_MIRANDA -15.72 -56.02 210 Napoli 40.83 14.30 118 Dahkla 23.72 -15.95 12 Neuchatel_Switzerland 47.00 6.96 487 Dakar_Aeronet 14.38 -16.95 0 Palaiseau_France 48.60 2.20 * Dalanzadgad 43.57 104.42 1470 Potenza_Italy 40.60 15.73 760 Davos 46.80 9.83 1596 Sofia 42.65 23.38 550 Dead_Horse 69.43 -148.70 332 Thessaloniki 40.60 22.97 60 Dharwar 15.43 74.99 700 Dongsha_Island 20.70 116.07 5 IPSL Lidar Network Dry_Tortugas 24.60 -82.78 0 Dunhuang 40.03 94.68 1300 Andoya 69.30 16.00 360 Egbert 44.21 -79.75 264 Dumont d'Urville -66.67 140.01 20 El_Arenosillo 37.10 -6.70 0 Haute Provence 43.94 5.71 590 El_Refugio -14.77 -62.03 225 La Reunion Island -21.80 55.50 * Eopace 36.18 -75.75 0 Palaiseau 48.42 2.16 * ETOSHA_PAN -19.17 15.90 1131 Flin_Flon 54.67 -101.69 305 MPLNET Gaithersburg 39.13 -77.28 50 Goa_India 15.45 73.81 20 Barbados 13.17 -59.50 0 Gerlitzen 46.66 13.90 1900 COVE 36.90 -75.71 0 GISS 40.78 -73.95 50 Dakar 14.39 -16.96 0 Gotland 57.92 18.93 10 GSFC 39.02 -76.87 50 GSFC 39.02 -76.87 50 Maldives 4.97 73.47 0 Guadeloup 16.32 -61.50 0 Moneterey 36.80 -121.79 0 Harvard_Forest 42.53 -72.19 322 Ny_alesund 78.93 11.93 11 Hamburg 53.57 9.97 105 Syowa -69.00 39.58 18 Helgoland 54.17 7.88 33 Hermosillo 29.08 -110.96 237 NDSC HJ_Andrews 44.23 -122.22 830 Homburi 15.32 1.53 0 Alert 82.50 -62.30 * Howland 45.20 -68.72 100 Andoya 69.30 16.00 360 IFT_Leipzig 51.35 12.43 125 Arkhar 64.60 40.50 * Ilorin 8.32 4.33 350 Dumont_d_Urville -66.67 140.01 20 IMC_Oristano 39.90 8.50 10 Garmisch 47.48 11.06 734 IMS_METU_ERDEM 36.55 34.25 0 GSFC 38.90 -76.70 50 Inhaca -26.04 32.91 73 Haute_Provence 43.94 5.71 * Inner_Mongolia 42.66 115.95 1343 Heiss 80.60 58.10 * Ispra 45.80 8.62 235 Kiruna 67.84 20.41 419 Izana 28.30 -16.50 2367 Laramie 41.30 -105.60 * Jabiru -12.66 132.89 30 Lauder -45.05 169.68 370 Jamari -8.63 -62.75 100 Mauna_Loa 19.54 -155.58 3397 Joberg -26.19 28.03 1736 McMurdo -77.85 166.63 10 JonesERC 31.23 -84.47 50 Ny_Alesund 78.92 11.93 15 Jornada 32.35 -106.52 1288 Okinawa 26.00 128.00 * Jug_Bay 38.77 -76.78 10 Poker_Flats 65.00 -147.00 * Kaashidhoo 4.97 73.47 0 Resolute 74.20 -95.00 * Kanpur 26.43 80.33 142 Reunion_Island -21.80 55.50 * Kaomi -14.78 24.78 1179 Salekhard 67.50 67.50 419 Kasama -10.17 31.18 1300 Scoresbysund 70.48 -21.97 10 Katibougou 12.92 -7.53 0 Sodankyla 67.37 26.65 100 Kejimkujik 44.38 -65.28 154 Sondrestromfjord 67.02 -50.72 180 Kolfield 39.80 -74.48 50 Suwon 37.20 127.60 150 KONZA_EDC 39.10 -96.60 457 Table_Mountain 34.40 -117.70 2300 Krasnogarsk 56.00 93.00 0 Thule 76.53 -68.74 30 La_Jolla 32.50 -117.15 0 Toronto 43.80 -79.50 * Lake_Argyle -16.11 128.75 150 Yakutsk 62.00 130.90 * La_Paguera 17.96 -67.03 0 Latoya -15.68 23.30 1064 REALM Lampedusa 35.52 12.62 45 Lanai 20.82 -156.98 80 CCNY 40.82 -73.95 * Lan_Yu_Island 22.03 121.55 348 Dalhousie_University 44.64 -63.59 * Lille 50.60 3.13 60 Ground_Winds 44.10 -71.16 * Lochiel 49.03 -122.60 0 GSFC 38.99 -76.84 * Los_Fieros -14.56 -60.93 170 Hampton_University 37.02 -76.34 * Lunar_Lake 38.38 -115.98 1908 Howard_University 39.00 -77.00 * Lydenburg -24.57 30.77 1186 MSC 44.23 -79.78 * Madison 43.07 -89.41 326 Penn_State 41.00 -78.00 * MALE 4.18 73.52 2 UAH 34.72 -86.64 * Mammoth_Lake 37.62 -119.03 2930 UMBC 39.25 -76.71 * Maricopa 33.07 -111.97 0 Marina 36.81 -121.81 15 USDA Marseille 43.27 5.37 100 Mauna_Loa 19.53 -155.57 3397 Alaska_Fairbanks 65.10 -147.40 510 Maun_Tower -19.90 23.55 940 Arizona_Flagstaff 36.10 -112.20 2037 McMurdo -77.63 162.88 75 California_Davis 38.50 -121.80 18 MD_Science_Center 39.27 -76.62 15 California_Holtville 32.80 -115.40 -18 Mexico_City 19.33 -99.17 2268 Colorado_Nunn 40.80 -104.80 1641 Miami 25.75 -80.20 0 Col_Steamboat_Spring 40.50 -106.70 3220 Midway_Island 28.20 -177.37 0 Florida_Homestead 25.40 -80.70 0 MISR_JPL 34.25 -118.25 450 Georgia_Griffin 33.20 -84.40 270 Missoula 46.91 -114.06 1028 Hawaii_Hilo 19.50 -155.60 3397 Modena 44.63 10.95 56 Illinois_Bondville 40.00 -88.40 213 Moldova 47.02 28.75 0 Indiana_West_Lafayette 40.50 -87.00 216 Monclova 25.95 -101.47 600 Louisiana_Baton_Rouge 30.40 -91.20 7 Mongu -15.25 23.15 1107 Maryland_Beltsville 39.00 -77.00 34 Monterey 36.80 -121.79 0 Maryland_Queenstown 38.90 -76.10 7 Mont_Joli 48.63 -68.15 30 Maine_Presque_Isle 46.70 -68.00 144 Moscow_MSU_MO 55.70 37.51 50 Michigan_Pellston 45.60 -84.70 238 MPI_Mainz 49.99 8.24 147 Minnesota_Grand_Rapids 47.20 -93.50 394 Munich_University 48.57 11.57 533 Mississippi_Starkville 33.50 -88.80 85 Mwinilunga -11.74 24.43 1430 Montana_Poplar 48.30 -105.10 634 Nauru_Aeronet -0.52 166.90 7 Nebraska_Mead 41.10 -96.50 353 NCU_Taiwan 24.88 121.08 0 New_Mexico_Las_Cruces 32.60 -106.70 1317 Ndola -13.00 28.66 1270 New_York_Geneva 42.90 -77.00 218 Nes_Ziona 31.92 34.78 40 Oklahoma_Billings 36.60 -97.50 317 New_York 40.77 -74.00 0 Ontario_Toronto 43.80 -79.50 80 Niabrara 42.77 -100.02 730 Saskatchewan_Regina 50.20 -104.70 580 North_Slope 69.63 -148.67 100 Texas_Panther_Junction 29.10 -103.50 670 Noto 37.33 137.13 200 Utah_Logan 41.70 -111.90 1368 NSA_YJP_Boreas 55.90 -98.29 290 Vermont_Burlington 44.50 -72.90 408 OceolaNF 30.21 -82.44 0 Washington_Pullman 46.80 -117.20 804 OkefenokeeNWR 30.74 -82.13 0 Wisconsin_Dancy 44.70 -89.80 381 Okinawa 26.35 127.77 46 Oostende 51.22 2.92 30 Individuals Orizaba 19.10 -97.32 3246 Osaka 34.65 135.59 50 Buenos_Aires -34.55 -58.50 15 Ouagadougou 12.18 -1.38 29 Davis_Station -68.58 77.97 * Owens_Lake 36.49 -117.87 1167 Dome_Concordia -75.10 123.29 3200 Oyster 37.28 -75.92 8 Hong Kong 22.34 114.17 44 Paddockwood 53.50 -105.50 503 Jabiru -12.66 132.89 30 Palaiseau 48.70 2.21 156 Kototabang -0.20 100.30 * Paris 48.87 2.33 50 Lake_Argyle -16.11 128.75 150 Penn_State_Univ 40.74 -78.08 401 NOAA_ETL * * * Philadelphia 40.03 -75.00 20 Ny Alesund 78.92 11.93 7 Pic_du_midi 42.94 0.14 2898 Potenza, Italy 40.65 15.81 770 Pietersburg -23.88 29.45 1200 Pune_India 18.53 73.85 559 Porco_Nacional -11.00 -48.00 210 Qingdao_ORSI 36.07 120.33 * Prince_Albert 53.20 -105.70 425 Quebec_Canada 46.88 -71.47 * Puerto_Madryn -42.78 -65.00 0 Quito 0.00 -78.60 * Railroad_Valley 38.50 -115.95 1435 Rio Gallegos -51.92 -69.23 0 Realtor 43.52 5.43 208 Rome_Tor_Vergata 41.84 12.65 130 Rimrock 46.48 -116.98 824 Sao_Paulo -23.56 -46.74 * Rio_Branco -9.95 -67.86 0 Tinga_Tingana -28.98 139.99 50 Rochester 44.23 -77.59 0 Trivandrum_India 8.55 76.95 6 Rogers_Dry_Lake 34.91 117.88 680 Zanjan 36.67 48.48 * Rome_Tor_Vergata 41.83 12.63 130 Roosvelt_Roads 18.20 -65.60 10 Rottnest_Island -32.00 115.28 40 Saclay 48.73 2.17 160 Sandy_Hook 40.45 -73.99 0 San_Nicolas 33.25 -119.48 133 Santa_Cruz -17.25 -63.23 225 Santiago -33.49 -70.72 510 Sao_Paulo -23.55 -46.73 865 Saturn_Island 48.77 -123.12 200 SEDE_BOKER 30.52 34.47 480 Senanga -16.11 23.29 1025 Seoul_SNU 37.45 126.95 116 SERC 38.87 -76.50 10 Sesheke -17.48 24.30 951 Sevilleta 34.35 -106.88 1477 Shelton 50.75 -98.76 563 Shirahama 33.68 135.35 10 Sioux_Falls 43.73 -96.62 500 Skukuza -24.98 31.58 150 SMHI 58.57 16.13 0 Solar_Village 24.90 46.40 650 Solwezi -12.17 26.36 1333 Sopot 54.45 18.55 0 SSA_YJP_Borea 53.68 -104.65 490 Steamboat_Spring 40.40 -106.80 2120 Stennis 30.37 -89.62 20 St_John_Island 18.32 -64.73 0 Sua_Pan -20.53 26.07 1100 Surinam 5.78 -55.20 0 Swakopmund -22.66 14.56 250 Tabes_Etal 43.22 0.05 332 Table_Mountain 34.38 -117.68 2200 Tahiti -17.56 -149.60 98 Tahoe_City 39.17 -120.14 1899 Tall_Tijmbers 30.66 -84.24 0 Tarbes 43.25 0.08 350 Tenerife 28.03 -16.63 10 THALA 35.53 8.67 1091 The_Hague 52.11 4.33 18 Thompson 55.78 -97.83 218 Tinga_Tingana -28.98 139.99 38 Tombstone 31.74 -110.05 1408 Toulouse 43.56 1.36 150 Toronto 43.97 -79.47 300 Tucson 32.21 -110.95 779 Uberlandia -19.90 -48.28 850 UCSB 34.42 -119.85 33 USDA 39.03 -76.88 50 Venise 45.30 12.50 10 Vinon 43.72 5.80 304 Walker_Branch 35.95 -84.28 365 Wallops 37.93 -75.47 10 Walvis_Bay -22.66 14.56 250 Waskesiu 53.92 -106.07 550 Xiang_He 39.75 116.95 36 Yulin 38.27 109.72 1080 Zambezi -13.53 23.11 1040

7.2 Expected number of coincident measurement opportunities during the 16 day repeating orbit of CALIPSO at each 10 degrees of latitude. Opportunities are given for separation distances of 10, 20, 40, 80, and 160 km between the CALIPSO ground-track and a validation site.

Latitude 10 km 20 km 40 km 80 km 160 km 0 0-2 0-2 0-2 0-2 3-4 10 0-2 0-2 0-2 2-3 4-5 20 0-2 0-2 0-2 2-3 4-5 30 0-2 0-2 0-2 2-4 4-5 40 0-2 0-2 0-2 2-4 4-6 50 0-2 0-2 1-2 2-4 6-8 60 0-2 0-2 2-3 4-6 8-10 70 0-2 0-2 2-4 5-7 10-14 80 2-3 3-6 6-12 13-24 24-58

7.3 Exchange Protocol for preliminary CALIPSO data

Protocol For Making CALIPSO Coincident Measurements

• Correlative measurements should be acquired as close as possible in time and location to the CALIPSO ground track. • Correlative measurements should be located as close as possible in space and time to the CALIPSO overpass. Intercomparisons should include an assessment of spatial and temporal matching errors. • Correlative measurements should be of comparable or superior accuracy and resolution to the CALIPSO measurements. • The primary CALIPSO validation period begins approximately 45 days after launch and ends about 18 months after launch. All CALIPSO data is considered preliminary until it is released to the public.

Protocol For The Exchange Of Information And Data

• The CALIPSO QPQ validation team will consist of correlative measurement investigators that actively participate in the acquisition and interpretation of observations for validation studies. • The CALIPSO QPQ validation implementation team will consist of those responsible for developing and implementing the QPQ validation program. • Members of the CALIPSO science and QPQ validation implementation teams will have access to the QPQ correlative measurement database. These data will not be made available to persons outside of these teams during the validation period without the expressed approval of the QPQ Principal Investigator (PI) for the correlative data set. Likewise, CALIPSO data shall not be provided to persons other than those scientists that have supplied coincident data without the expressed approval of the CALIPSO PI. • QPQ validation network PIs will have access to data products from the CALIPSO mission that are coincident with the validation data that have been made available for comparison. The CALIPSO data will be distributed in segments of a half-orbit or less that overlap with the QPQ site. • Predictions of overpass times for all QPQ validation network sites will be updated on the QPQ validation website (http://calipsovalidation.hamptonu.edu) once per week. The status of the CALIPSO satellite will also be available at this site. • Members of the QPQ validation team should submit a "Request For CALIPSO Data" to the Atmospheric Sciences Data Center at http://eosweb.larc.nasa.gov and the appropriate coincident CALIPSO data products will be forwarded to the requestor. • Members of the QPQ validation team without a data archive that is readily accessible to the CALIPSO science and validation implementation teams, should upload their data to Hampton University's QPQ data archive. These data should conform to the common data format specified by the QPQ validation coordinator. Data products submitted to this server can be updated by the QPQ validation team member as often as needed. The data will be considered as “Preliminary” until the CALIPSO team is notified that they are ready for public distribution. • QPQ correlative measurement data set will be archived at a public facility following the validation phase of the mission. Data submitted to this public archive is voluntary.

Protocol For Publishing CALIPSO Data Comparisons

• The criteria for publication shall be the ability to make a definitive statement on the quality of the CALIPSO data products based upon comparisons between the QPQ validation network and CALIPSO data. • Manuscripts that include observations from the QPQ validation network and CALIPSO for publication in peer-reviewed journals and conference proceedings shall include, as authors, scientists involved in the preparation of the measurements and their interpretation. The manuscript must be circulated to all co-authors for review and approval. PIs/Co-Is responsible for generating a measurement or a data product from a QPQ validation site shall be offered the right of co-authorship. • Presentations of these data and findings in public meetings may be made subject to the approval of the coauthors. • Publication of preliminary CALIPSO data products requires co-authorship with a CALIPSO Science Team member and approval of the CALIPSO PI and Co-PIs.